Speed regulator



G. E. HOWARD 2,289,014

SPEED REGULATOR July 7, 1942.

Filed July 1, 1941 4 Sheets-Sheet l INVRMTOR July 7, 1942.,

G. E. HOWARD SPEED REGULATOR Filed July 1, 1941 4 Sheets-Shejt 2 July 7, 1942. c. E. HOWARD SPEED REGULATOR Filed July 1, 1941 4 Sheets-Sheet 3 y gINVENTOR M fia/a m July 7, 1942. G E HOWARD 2,289,014

SPEED REGULATOR Eiled July 1, 1941 4 Sheets-Sheet 4 Patented July 7, 1942 UNITED STATES PATENT OFFICE SPEED REGULATOR George E. Howard, Butler, Pa. Application July 1, 1941, Serial No. 400,698

21 Claims.

throttle, valve, ,the piston being spring-biased ure of the total fuel intake past the fuel supply valve and is related to the speed of rotation of the engine but not to the horse power developed by the engine under all conditions. The fuel passing the fuel valve dependsupon the area of opening of that valve and the difference between the pressure above the valve which is approximately atmospheric and the pressure below the valve. This latter is determined by the volumetric displacement of the engine cylinders acting as a pump reducing the pressure to sub-atmospheric, because of the inability of sufiicient fuel to pass the valve opening without a drop in pressure due to the resistance in passing this valve opening.

On the other hand, the power of the engine is determined by a number of things, principally the efilciency of the explosion of the fuel mixture drawn into the cylinders as previously described. This efficiency has no exact relation to the suction or pumping action of the cylinders drawing in the fuel mixture. Therefore, if for any reason, as for instance the failure of a spark plug to ignite a single cylinder, the power of the engine will be reduced although the amount drawn into the cylinders will be the same. This reduction of power will therefore slow down the automobile, and the vacuum in the manifold is thus not an expression of the speed of the vehicle.

Achange in the opening of the fuel supply valve will cause a change in the intake manifold pressure, and, under a constant condition, a change of power and a change of speed will result. However, the fuel supply valve may remain fixed in position and the vacuum in the manifold may remain constant and the speed vary considerably even though all other conditions are the same, except the load. This is especially true in going down or in climbing a steep hill, when the engine is either idling or is running at nearly full power. This makes this type of speed control unsatisfactory.

- equalize this condition.

manifold vacuum and the engine horse power may have a fairly uniform relationship and the vacuum force on a cylinder biased by a spring may have an equally constant relationship, the valve opening and the intake manifold vacuum do not have such a relationship. At light loads the valve opens slightly for considerable increases in the fuel admitted to the engine, while at heavy loads the reverse is true and the valve opens widely for relatively small increases in the engine horse power. Approximately, a butterfly valve will supply about 80% of the power for the first 30 degrees of angular valve travel, and the remaining 20% will require a 40 degree opening. Roughly this represents two stages of opening, but neither of these stages is a straight line relationship between valve opening and power, but follows a sort of characteristic curve well known to the art. A number of intermediate devices between the fuel valve and the springbiased piston or diaphragm are employed to One plan is to have two or more springs of different character so that they exert a different opposing force for each unit of lineal distance traveled for the two stages above outlined. This may approximate a desired condition but is not sufliciently close to be satisfactory.

Another method is to use a cam whose travel is proportioned exactly to these two stages of relationship and it may also be so conformed as to follow the characteristic curve of the two separate stages. However, a cam with such divergent contour as to give this relationship is impractical and causes a great deal of friction and wear, and otherwise interferes with proper operation.

Owing to one or more of these above-mentioned reasons, these governors are not satisfactory as to maintenance of constant speed. They are jerky and considerably overrun and underrun the desired speed.

All devices of this kind have friction, and this friction is increased when parts become dry and worn or dirty, or dust interferes with their proper operation. The friction may be fairly light, but it has to be overcome twice. It resists a movement one way and then another.

In the case of a governor which employs a spring-biased piston, a change-in speed caused by a change in load will result in unbalancing of the spring and vacuum force, through changes in manifold vacuum, tending to move .the throttle valve towards balanced position, but

Another objection is that while the intake the force resulting from this speed change is insufflcient to overcome friction of the parts, therefore preventing the balancing of the vacuum and spring forces and hence preventing movement of the throttle valve to a position of balance with respect to the desired speed.

Variation in the set or desired engine speeds must be small for satisfactory operation. Such variations make little difference in the manifold pressure, at any desired speed setting or for any load condition at said set speed. There is, therefore, not sufficient change in suctional force to overcome changed spring resistance, plus the friction. For example, tests of an engine in a standard automobile show that on a level road, at 50'miles per hour set speed, a range from 49 m. p. h. to 51 m. p. h. causes a change of only 4 lb. per square inch in intake manifold pressure. At both heavier and lighter loads (as on grades) the diiference in pressure is even less.

By my arrangement as hereinafter described, at a set speed of 50 m. p. h. and a variation of 49 m. p. m. to 51 m. p. h. the vacuum change may be as much as 8 lbs. (or any desired fraction thereof) per square inch. In an actual test of the same automobile this difference was 6 lbs. per square inch, as compared to the lb. above mentioned, which enabled the automobile to remain within the speed limit of 49 to 51 m. p. h., under all load conditions. A regulator of the spring-biased piston and suction-operated type, on the same automobile, produced a variation of 15 miles per hour instead of 2 m. p. h.

One object of my invention is to provide means whereby a governor of the suction type can be employed to operate a throttle valve in such manner as to maintain a proper relation between load change and fuel supply, at all positions of the valve.

Another object of my invention is to provide an arrangement whereby the governor will be operated in accurate relation to changes in engine speed, notwithstanding the absence of any definite relationship as between changes in speed and vacuum conditions in the manifold.

Another object of my invention is .to provide means whereby upon indication of load change which will require increase of fuel in order to maintain a desired speed, additional fuel will automatically be supplied without the delay incident to operation of the throttle valve by the governor.

Another object of my invention is to provide means whereby the effectiveness of the suctional force in an intake manifold or the like will automatically be changed at predetermined changes in engine speed.

Another object .of my invention is to provide means whereby frictional resistance does not require an extreme change of speed to overcome it but instead a slight change of speed may produce a force suflicient to overcome the friction and the change in resistance in the spring occasioned solely by the change in speed.

A further object of my invention is to provide means for equalizing the functional valve-opening relationship to biased diaphragm or' piston linear travel, so as to avoid undue friction or wear in the conventional type of cam commonly employed.

In the accompanying drawings Figure 1 is a side view of an automobile engine equipped with my invention; Fig. 1a. is an enlarged view of the throttle-operating pedal of Fig. 1; Fig. 2 is a view on an enlarged scale of the fuel intake line movable parts in a different position than shown in Fig. 1; Fig. 3 is a view partially in elevation and partially in section of certain of the valveoperatlng mechanisms of Fig. 1, but on an enlarged scale; Fig. 4 is a view showing a modification of the by-pass structure of Fig. 1, on an enlarged scale; Fig. 5 is a sectional view on an enlarged scale, showing a somewhat difierent arrangement of the by-pass, from the upper side to the lower side of the throttle valve than that shown in the other figures; Fig. 6 is a schematic view showing a somewhat different form of speed responsive device for controlling the bleeder or by-pass valve; Fig. 7 is a sectional view on an enlarged scale of the centrifugal governor shown in Fig. 6, and takenon the line VIIVII of Fig. 8; Fig.8 is a view taken on the line VIII-VIII of Fig. 7; Fig. 9 is a plan view of the strutor pusher bar of Fig. 7; Fig. 10 shows a modification of the governing apparatus of Fig. 1, and Fig. 11 shows an arrangement whereby a weight element movable by gravity is employed to vary the relationship of vacuum and atmospheric pressures.

As shown in Fig. 1, the apparatus is employed in connection with various conventional parts of an automobile engine, such parts including the usual fuel intake line N) that leads from a carburetor (not shown) to the intake manifold ll. of the vehicle, a throttle valve [2 being provided to normally control fiow of fuel to the engine. A crank arm I3 is rigidly connected to the shaft of the throttle valve and is normally biased tothe rear end of the portion 25 and against a thrust collar 21 that is formed on a pull rod 28, the pull rod being connected to the arm l3 of the throttle valve l2. Through the connections just described, the springs l4 and I5 tend to hold the throttle open.

The throttle is normally held closed, however, by a spring 30 which is secured to a floor board 3| of the vehicle and to one arm of a lever 32 which is mounted on a fixed pivot 33. A link 34 connects the crank member 32 with an arm 35 that is loosely mounted on the shaft 36 of the throttle valve l2 and abuts against the adjacent edge of the arm 13. The tension of the spring 30 is such that it will overcome the pressure of the spring .26 and therefore hold the throttle valve closed. When the throttle pedal 81 is depressed to rock the lever 32 against the tension of the spring 30 and thereby withdraw the arm 35 from engagement with the arm l3, the springs 4-,|5 operating through the link 24 and the spring 26 will move the throttle valve l2 to open position a distance determined by the extent to which the pedal 81 has been depressed. The spring 26 permits closure of the throttle valve by the spring 3|], regardless of the position occupied by the link 24 and its associated parts.

The fuel supply to the engine will flow through the intake line 10 and through the manifold H in the usual manner, at a rate normally dependent upon the position of the throttle valve l2.

and the by-pass conduit of Fig. 1, but with the In order to provide for automatic control of the fuel supply in accordance with speed and load conditions, I employ a by-pass conduit ll leading from above the throttle valve to a point below the same. A suction line It leads from the conduit II to the diaphragm casing It, so that suctional or subatmospheric pressure in the manifold II will be transmitted to the casing It, tending to move the diaphragm 40 in opposition to the pressure of the springs i4-II. If this suctional force is sufllcient, the diaphragm will be moved to the left and the bell crank lever 2l2 l.swung in a counter-clockwise direction-by a biasing spring 4|, so as to exert a pull upon the arm ll of the throttle valve i 2 and thus move the valve toward its closed position. Obviously a piston could be employed phragm.

The conduit 38 not only serves as a fuel by pass, but as a bleeder whereby the suctional force exerted from the manifold through the pipe 39 will be modified. The extent of bleed is controlled by a valve 42 in the by-pass conduit 38. For example, when the valve 42 is closed or nearly closed, substantially all the. suctional force in the manifold will be exerted on the diaphragm 40. This, in turn, makes a difference in the lineal travel of the piston or diaphragm operating the throttle valve. A biasing spring offers a uniformly increasing resistance to the lineal travel of the piston for each increment of travel.

Therefore, the ordinary biasing spring will not I synchronize the movement ofthe valve to correct this difference between open and closed position. As previously stated, 30 degrees of angular travel from opening will supply 80% of the fuel, while the remaining 40 degrees of opening will supply the remaining 20% of the fuel. Therefore, tandem springs of different strength have been employed to roughly compensate for these two stages.

While I have shown a tandem spring arrangemen to overcome to some extent the opposition to the use of a single spring for opposing diaphragm movement, I provide still another correcting device, namely the cam 20. The spring I4 is a light spring and the spring I considerably heavier. When suctional force is first exerted within the casing IS, the diaphragm 40 will be pulled to the left, thereby compressing the spring I4. Upon engagement of the thimble or spring seat 44 with the spring seat l'l, further suctional force will compress the spring l5, thus permitting relatively less movement of the diaphragm 40 as the valve l2 moves toward its closed position, whereby there will not be excessively rapid reduction in fuel supply.

However, even this does not produce a desired biasing movement of the diaphragm in accordance with the manifold vacuum, and therefore I have provided the cam whose camming surface is so curved as to correct the difference that exists as between the correct amount of movement of the throttle valve and the movement which would actually take place therein under a given suction condition where only springs are employed. The curvature of the cam surface is such that as the diaphragm moves to the left under suctional force, the crank arm 2|, when the throttle valve is near its closed position, will be swung by its spring 4| through a shorter distance as the spring l5 becomes further compressed than at earlier stages in the diaphragm movement. To this end the cam surface 20 is given a different radius of curvaturenear its lower end than at its upper portion. Adjustment instead of the dia-- of the springs l4 and II relative to the diaphragm 40 is effected by a screw plug 4|.

Movement of the diaphragm to the right is limited by the collar lid and the huh I of the casing ll. Movement to the left is limited by an adjusting screw 45a. when the adjusting screw 45 is moved, a corresponding adjustment must be given to 45a to keep the movement of the shaft is the same. Adjustment of the arm 2| relative to themain valve l2 may be eflected by any well-known means (not shown), as for example, on its shaft 22, or a turnbuckle on the rod 24.

As another means for varying the effectiveness of the suctional force on the diaphragm 4| as between the wide openand more nearly closed positions of the throttle valve i2, I provide a valve 41 which is movable to restrict movement of the fluid pressure in the pipe 39. This valve has a crank 48 which is connected through a link 4! -with the arm I 3 of the valve l2, so that as the valve l2moves toward its closed position, the valve 41 will also be moved, to restrict flow through the pipe The result is that the suctional force from the manifold will not be so effective upon the diaphragm 40 and there will be slower angular movement of the valve l2 at points near its closed position than at its more widely open positions. The valve 41 is supplemental of the combined spring and cam arrangement in the diaphragm casing, above described, and may be dispensed with.

As a means for preventing pulsations of vacuum force being too readily transmitted ,to the diaphragm, and in order to retard such force to a desired extent, I provide a valve 50 which may be set at a desired point of restriction.

The valve 42 which is provided in the by-pass 38, serves not only to by-pass fuel to the intake manifold at certain times, as will be hereinafter explained, but also to admit bleed air or fuel mixture at substantially atmospheric-pressure to control the effectiveness of the manifold suction at the pipe 38, the extent of such bleed being determined, of course, by the position of the valve 42. Thus when the valve is closed, the full force of the manifold suction will be exerted upon the diaphragm 40, at a rate dependent upon the positions of the valves 41 or 50 and the position of another valve 52 in the lower end of the bypass 38. The valve 42'is mounted on a shaft 53 that extends through the walls of the by-pass 33. The outer end of the shaft has keyed thereto a disc 54 so that as said disc is oscillated, the valve will be opened and closed. A spring 55 constantly urges the valve toward its open position. A lever 56 is loosely mounted on the shaft 53 and has connection through a link 51 with th arm H of the throttle valve i2, the link 51 being made in two parts adjustably connected by a tumbuckle 58, so that the arms l3 and 55 may be angularly adjusted with respect to one another. The arm 56 carries a stud 59 in position to engage against a stop shoulder on the disc 54, so that when the valve I2 is moved toward closed position, the valve 42 will also be moved toward its closed position. The adjustment of the turnbuckle 58 is such that, as shown more fully in Fig. 2, the valve 42 may, if desired, be still partly open when the valve [2 is fully closed, and there may, therefore, be some by-passing of fuel around the valve I2, although ordinarily the valve 42 will be fully closed by the speed-responsive elements to be hereinafter described. For example, the angularity of the valve 42 relative to the valve l2 may be such that approximately 5% to 20% of the fuel supply will normally be by-passed when these valves are in the positions shown in Fig.2.

The valve 42 can be moved to its closed position, independently of the lever arm 66 and. the valve I2, and against the tension of the spring 56, by a solenoid 6! and its movable core 62, the core 62 being connected to the disc 54 by a link 63. The energization of the coil GE is controlled by a speed-responsive device in a manner which will now be described. As shown in Fig. 1, the speedresponsive device comprises an electrical generator 65 that is provided with a pulley 66 driven by the fan belt 61 or by some other connection with the crank shaft. The generator voltage will be in accordance with the rate of engine speed. The generator is connected through conductors 68, a rheostat 69' and conductors 16, with a solenoid coil If that has a plunger 12 which is normally in its lower position. Upon energization of the solenoid H to a predetermined degree which is determined by the setting of the rheostat 6B, the core 12 will be moved upwardly to push a spring-biased switch contact member 13 into engagement with a switch contact member 14, to thereby close a circuit through a battery 15, conductors I6 and the solenoid 6|, and thereby caus-- ing the core 62 to be moved downwardly and the valve 42 to be thereby closed. Miles per hour speed of the engine at which'these movements take placeiwill, of course, be determined by the setting of the rheostat 69.

When the vehicle reaches or exceeds a predetermined speed, the valve 42 will thus be moved to fully closed position, thereby rendering the suctional force in the intake manifold entirely effective to actuate the diaphragm 40 and move the valve f2 toward closed position. Reduction in speed is thus effected and the energization of the coil 1! reduced, so as to permit opening of the switch 13-716, whereupon the valve 42 will be opened by the tension -of its spring 55. This change takes place immediately upon predetermined reduction in speed, and fuel is thereby immediately by-passed past the valve 42, so that there is no substantial lag and unnecessary reduction in speed before the diaphragm 40 can act to increase the fuel supply. In other words, there is a sudden by-passing of a definite percentage of the total fuel supply upon indication of a load change. Added load, of course, slows the engine down and the speed control device immediately responds to provide increased power. This increase being perhaps not more than of the total fuel supply, avoids too sudden increase in power such as would cause overrunning of the fuel supply in both directions, therefore avoiding overrunning and the setting up of rhythmic or fluttering action such as frequently occurs when the fuel supply is controlled entirely by a governed throttle valve. Furthermore, as above stated, the governing apparatus for a throttle valve usually operates too slowly, so that there is a lag between speed change and change in rate of fuel supply, which results in too great a swing above and below the governed speed. I have discovered that the sudden addition of a substantial amount of fuel (by-passed) and power can be made with substantially no change of load and without appreciable effect upon the smoothness of travel of the car.

The coil 6! and the core 62 may have such close fitting relation that they function as a dash-pot to prevent snap movements of the valve 42. It

will be seen that at any position of the valve l2 if the speed exceeds the predetermined rate, the coil 6| will be energized to close the valve 42, since the stop shoulder on the disc 54 will be moved away from the stop pin 59. On the other hand, the stop pin 59 limits the extent to which the valve 42 can be opened relative to the valve I2.

The valve 52 has a screw threaded adjustment whereby it may be set to a position so that there will be proper relationship as between themanifold vacuum and the by-pass 38. Certain engines and fuels require a somewhat different adjustment as between the by-passed fuel and the main fuel supply than others: The provision of the valve 52 therefore permits a given by-pass apparatus to be employed with various types of engines and kinds of fuel, to not only effect control of the amount of by-passed fuel, but also to effect proper adjustment of suction pressures in the pipe 39.

As stated above, the by-pass valve 42 may be partly open at a time when the throttle valve 12 is completely closed, as under light load conditions when traveling down grade, this because of the fact that the suctional force will'be greater under light load conditions. The amount of fuel by-passed at such a time may be only sufficient for ordinary idling of the engine, though in descending a hill the vehicle transmission mechanism frequently will drive the engine at faster than idling speed. When the vehicle speed, and consequently the engine speed, exceeds the governed rate under these conditions, the solenoid 6f will be energized to completely close also the valve 42, thus not only facilitating reduction in speed, but also effecting a saving of fuel.

With the throttle valve I2 closed and the bypass valve 42 fully closed or nearly closed, or from other causes, there may occur accumulation of unburned gases or fuel in the muffler ll. In

1 order to avoid muffler explosions when the cylinders again begin firing explosive mixture received from the manifold II, I provide means for scavenging the muffler I7 (Fig. 1) of unburned fuel, and to this end make an opening in the front side of the muffler that is kept closed by a flap valve lla during normal functioning of the muffler. A flaring air scoop 11b is provided at the front of the said opening to direct air past the valve 11a into and through the muffler when the vehicle is traveling at a substantial rate of speed, thereby keeping the muffler clear of unburned gases when the cylinders are not firing.

In Fig. 4 I show a modification wherein a second valve 18 is provided in the by-pass 38. This valve is mounted on a shaft 19 to which is rigidly secured a lever 80 that is connected with the link 51. Valves 42 and T6 are arranged so that although moving in thesame clockwise direction, they are in reverse functionally. A movement of shaft 53 clockwise will open valve 42, while closing valve 18 and vice versa. Thus I get the full benefit of either the manifold vacuum or the substantially atmospheric pressure of the fuel passing valve 42 through pipe 39 which controls diaphragm 40. The pressure in passage 39 is a composite of the substantially atmospheric pressure passing 42 and the intake vacuum passing valve 18.

If valve 42 opens as valve 18 closes, the pressure in 39 would more closely approximate the substantially atmospheric pressure above the main fuel valve I2 and vice versa. These two valves can be set at any desired angular relationship and can be arranged so that either may be entirely closed or that neither be entirely closed nor fully open. Thus is provided leeway for providing the right pressures in 39 for the operation of the device and at the same time enables a substantial amount of bypassed fuel to be effective except when the core 62 is energized due to the maximum desired speed being reached by the engine. The by-passed fuel increases the power, when the valve 42 is opened through increased load, and there will be a decrease of power upon decrease in load.

In Fig. I show details of a by-pass arrangement for the purpose of avoiding turbulence of flowthrough the intake line I0 and the causing of unbalanced forces on the throttle valve I2 by such flow. Although the valve I 2 will normally be geometrically balanced about its shaft 36, even a fairly smooth flow of fuel mixture through the pipe I0 creates unbalanced thrust forces on the valve which may interfere with the accurate functioning of the governing of the diaphragm. In this arrangement I provide a fitting having an upper header chamber 82 into which angularly arranged ports 83 lead from above the valve,and a lower header chamber 94 with which the intake line I0 communicates through ports 35, below the throttle valve. The passageway 30a leading from the upper header 82 to the lower header 84 corresponds to and functions in the same manner as the by-pass 39. Similarly the valve 42a may be operated in the same manner as the valv 42,

In order to permit driving of the vehicle without the speed limitation imposed through the use of the speed-responsivegenerator 65, I provide a switch 86 (Figs. 1 and 1a) in one side of the line 60. This switch is carried by the foot pedal 01. When the driver wishes to render the governor ineffective so that he may increase the speed of the vehicle, as when a burst of speed may be required in order to pass another vehicle or in order to avoid a collision, he will place his foot upon a button 08 and depress it to move the spring-like contact 89 of the switch out of engagement with the contact member 90, thereby breaking the circuit through the solenoid II and rendering such solenoid ineffective to cause energization of the solenoid 6|. In such case the valve 42 will always be left partially open to the extent permitted by the valve I2, so that there will be such bleed through the by-pass 38 and to the suction line 39 as will prevent the manifold suction from being effective to operate the diaphragm 40.

A latch 92 is provided for releasably holding the foot pedal 81 in depressed position, so that the driver, under normal open-road conditions, will not have to hold a foot on the accelerator pedal. The latch can be operated by the driver's foot through the medium of a latch lever 93, which is fully shown and described in my Patent 2,239,962 and therefore need not be here explained in detail. Similarly, as shown in said patent, the latch will be automatically tripped through depression of the brake pedal 94, so that the latch 92 will be automatically tripped when the brake is applied, to cause the spring 30 to close the throttle valve I2, the force of the spring 30, as above explained, being greater than the capacity of the spring 26.

From the foregoing it will be seen that under open-road driving conditions,-where a speedof perhaps 50 miles per hour is permissible, the

driver needs only to depress the pedal 91 to latch it in depressed position, whereupon the vehicle will automatically be maintained at approximately the desired speed, regardless of changes in grade, wind etc. Should he desire to restrict the vehicle to full manual control, he need simply depress the latch lever 93 and operate the pedal 01 in the usual manner.

In Figs. 6 to 9, I show a centrifugal governor 96 as the speed-responsive element instead of the generator 65. The governor 98 is driven by a pulley 9! in the same manner as the pulley 66 and is provided with weighted elements 93 that are pivotally mounted at 99 on the rotatable body member I00 of the governor, which body member is rigidly connected to the shaft IOI of the pulley 91. The tail pieces of the elements 96 are notched for engagement with an end of a push bar I02, whose other end extends into a recess In a lever I03 that is mounted on a fixed pivot I04 to a suitable support on the engine. A spring I 05 is connected to the upper end of the lever I03 and is adjustable by a screw I06, so that the speed at which the governor becomes effective to swing the lever I03 can be adjusted. The screw I06 may be extended to the dash, to be operated for the same purpose as rheostat 69, i. e. to adjust the governor 96. The lever carries a switch contact element I01 that is moved into and out of engagement with a switch contact member I08, to thereby control a circuit through a line I09, a battery H0 and a solenoid II I, which corresponds to the solenoid 6|, for operating the by-pass or bleeder valve 42, so that when the engine speed exceeds a predetermined rate, the governor will close the circuit through the solenoid II I, to thereby effect closure of the valve 42 and thus provide desired manifold force through the suction line 39 to the diaphragm 40. In this case as in the arrangement of Figs. 1 and 1a, the pedal is provided with a switch II2 operated by the drivers foot through a push button I I3 when it is desired to render the governor ineffective to establish a circuit through the solenoid II I.

In Fig. 10 I have shown a modification of the arrangement of valves in the by-pass, somewhat different than those shown in Figs. -1 and 4, whereby I am enabled to automatically effect variation in the relation of vacuum force from the manifold and atmospheric pressure, in accordance with changes in load conditions and the movements of the throttle valve. In other words, the effectiveness of the suctional force from the manifold upon the governing diaphragm or piston is varied in accordance with certain movements of the throttle valve I2. In this arrangement the by-pass II5 corresponds to the by-pass-36 of Figs. 1 and 4. suctional force from the intake manifold is normally transmitted into this by-pass and through the pipe 39 to the diaphragm casing I6. A control valve H6 is provided, which will close the connection between the by-pass H5 and main fuel intake I0. A spring III' normally holds this valve in open position.

When the speed of the vehicle exceeds a predetermined rate, a solenoid II9 which corresponds to the solenoid 6I is energized to pull downwardly a link II9 which has crank arm connection with the valve I I6, to close the valve. Therefore, whatever suctional force exists in the manifold at such an over-speed condition, is fully effective to move the throttle valve I2 toward closed position.

The pull rod 28 which operates the throttle valve has an extension I20 that is slidable through an opening in one leg I2I of a, bell crank lever. A stop collar I22 has set screwadjustment longitudinally of the rod I20, so that when the rod 28 is pulled a predetermined distance in a direction to open the throttle valve I2, the collar I22 will engage the bell crank leverto rock the same. The bell crank lever is rigidly secured to the shaft I23 of a valve I24 and has connection through a link I25 with an arm I26 that is rigidly connected to the shaft I21 of a valve I28. A spring I29 that is connected to the bell crank lever and to any suitable fixed point normally holds the valves I24 and I28- in the position shown. At such positions, the valve I24 is only slightly open and the valve nearly fully open, so that the suctional force from the manifold will be more fully effective to actuate the governor than when the valve I24 is at a further open position and the valve I28 more toward its closed position. In the latter instance, of course, there will be an increase in the amount of atmospheric air admitted and a restriction of the suctional flow at the valve I28.

An adjustable screw stop I3I is provided to limit the extent to which the valve I24 may be closed, and hence the extent to which the valve I28 will be opened under the pull of. the spring I23, this because movement of the valve I24 toward closed position results in movement of the valve I28 toward open position and vice versa.

When heavier loads occur with consequent reduction in engine speed, the valve I2 will be move doward open position in order to secure the full power of the engine. This movement is faciltiated through reduction in effectiveness of the suctional force in the intake manifold, because during travel of the pull rod 28 to open the valve, the stop collar I22 will engage the bell crank lever I2I to rock it, thus opening the valve I24 to admit flow at atmospheric pressure and moving the valve I28 toward closed position to reduce the suctional flow. The suctional force in the pipe 39 is thereby greatly reduced, to perhaps an inconsequential amount, and the valve I2 will therefore more readily be moved to secure the desired full power of the engine.

Referring now to Fig. 11 I show a modification of the structure of Fig. 10, particularly with respect to the matter of automatically varying the relative volumes of fluid at atmospheric pressure and fluid under subatmospheric pressure in the by-pass, and hence controlling the degree of suctional force exerted upon the fluid-pressureoperated governor, upon various changes in road conditions.

In ascending a hill, a greater output of energy is required from the engine than when traveling on a level road. Consequently it is not desired that the suctional force that tends to close the throttle valve be so great as to prevent free opening of such valve. Therefore, the present arrangement provides for the reduction of the suctional force that tends to move the throttle valve toward closed position, so that the said valve may open more freely, to give the required additional power. On the other hand, in descending a hill, it is desirable to have the suctional force more fully effective to readily move the throttle valve toward closed position.

As shown in this Fig. 11, the apparatus includes a valve H6 and an electromagnet II8 that function in the same manner and serve the same purpose as the corresponding members in Fig. 10. It will be understood that in both Figures 10 and 11, a centrifugal governor can be substituted for the electromagnet II8, to close the valve I I6 at abnormal speeds and to thereby render the suctional force fully effective to close the throttle valve. Valves I33 and I34 in the by-pass I35 function somewhat as do the valve I24 and I28 of Fig. 10, to modify the effect of the suctional force from the intake manifold to the pipe 39 that leads to thegovernor diaphragm. A hub I36 is secured to the shaft I31 that carries the valve I33 and has forked arms I38. The hub I36 is rotatably adjustable on the shaft I3I by a set screw I39, so that the hub and the valve can be angularly adjusted to provide for a desired degree of valve opening when the forks I38 are at their mid or neutral position.

A pendulum-like weight MI is mounted on the shaft I 42 that carries the valve I34, and is angularly adjustable on the shaft I42 by a set screw I43. The shank of the weight I4I has a series of holes I44 for the reception of a screw or stud I45 which can be set in any of the holes and engages the arms I38, so that when the weight I4I swings in one direction to rock the valve I34, the valve I33 will be rocked in the opposite direction, the positioning of the screw I 45 serving to determine the relative ranges of movements of the valves.

When traveling along a level road, the valves I33 and I34 may suitably occupy the positions shown in Fig. 11, they being so set that the vacuum force will be properly effective to control the speed of the vehicle, it being understood, of course, that the valve H6 is normally open. However, when ascending a hill, at which time it i desired that the fluid pressure governor shall not unduly restrict free opening movement of the throttle valve I2, the weight I4I will swing in a counter-clockwise direction as viewed in Fig. 11, thus moving the valve I34 toward closed position and the valve I33 toward open position, thereby modifying and restricting the suctional force from the manifold. 1

1n descending a hill, the weight I4I tends to swing in a clockwise direction, to more fully open the valve I34 and to move the valve I33 toward closed position, thus intensifying the vacuum force transmitted through the pipe 39 to the governor diaphragm. However, this movement in a clockwise direction need perhaps not be as great as movement in the other direction, since theoretically the valves I33 and I34 have a setting with respect to the weight I4I, as shown on the drawing, that provides for proper control under lighter loads, as when running on the level or descending a hill.

position and the weight I4I loosely mounted on the shaft I42, so that the weight will rock only the valve I33 for the purpose of admitting more or less fluid pressure at atmospheric pressure to modify the suctional force under changes in grade. Also, the weight I4I can be rigidly connected to the shaft I42 and the stud I45 re-- moved so that the weight will rock only the valve I34. In such case, the valve'l33 would be set at a fixed position.

The term atmospheric pressure is used in the accompanying claims in a broad sense and for convenience of recital, since the fuel mixture which enters the by-pass from a point in advance of the throttle valve is actually at somewhat less than atmospheric pressure, owing to the friction of the air when passing the air strainer, the carburetor and along the walls of the passageway.

I claim as my invention:

l. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the easing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve for controlling the rate flow through said pipe, and a connection between said valve and the throttlevalve whereby the rate of flow through the pipe is varied in accordance with the'position of the throttle valve.

2. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the easing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve for controlling the rate of flow through said pipe, a connection between said valve and the throttle valve, whereby the rate of flow through the pipe is varied in accordance with the position of the throttle valve, and means for admitting fluid at atmospheric pressure to the conduit in predetermined relation to changes in position of the throttle valve.

3. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve for controlling the rate of flow through said pipe, a connection between thesaid valve and the throttle valve, whereby the rate of flow through the pipe is varied in accordance with the position of the throttle valve, and means for admitting fluid at atmospheric pressure to the conduit in predetermined relation to changes inengine speed.

4. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle -valve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a connection between the throttle valve and one of the other valves for changing the. position of said other valve in accordance with changes in position of the throttle valve.

5. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow oi motive fluid to the engine, of' a conduit leading from the pasageway at a point between the valve and the engine, a casing,

a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle va;lve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a connection between the throttle valve and the other valves whereby the positions of said other valves are changed in accordance with change in position of the throttle valve,

6. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow between V the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a connection between the throttle valve and the valve which admits fluid at atmospheric pressure, for changing the position thereof in accordance with changes in position of the throttle valve.

7. The combination with a motor vehicle driven by an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a weight element movable through changes in road grades, having connection with one of said last-named valves for moving said one valve.

8. The combination with a motor vehicle driven by an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a weight element movable through changes in road grades, having connection with both of said last-named valves, for moving them.

9. The combination with a motor vehicle driven by an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing communicating with the conduit, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, means for controlling the effectiveness of the suctional force in the passageway upon the element in the casing, and a weight element movable through changes in road grades, for varying the effectiveness of said means.

ll. The combination with a motor vehicle driven by an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flowbetween the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a weight element movable through changes in road grades, having connection with both of said last-named valves, for moving them, the operating connections between the weight element and the valves being so arranged that when either valve is being moved toward closed position, the other valve is being moved toward open position.

12. The combination with an engine having an intake passageway provided with a throttle valve for controlling fiow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow through said pipe, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, and a device responsive to engine speeds above a predetermined rate, for shutting off admission to the conduit of fluid at atmospheric pressure.

13. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, means responsive to changes in load conditions for moving one of the last-named valves, and means responsive to engine speeds above a predetermined rate, for shutting of! admission to the conduit oi fluid at atmospheric pressure.

14. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve, a valve controlling flow between the passageway and said conduit, a valve for admitting fluid at atmospheric pressure to the conduit, whereby a desired relation as between atmospheric pressure and suctional force from the said passageway may be secured, means responsive to changes in load conditions for moving one of the last-named valves, another valve for controlling admission of fluid at atmospheric pressure into said conduit, and means responsive to engine speeds above a predetermined rate, for closing the last-named valve.

15. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing communicating with the conduit, an element in the casing movable under suctional forces in the conduit to move the valve toward closed position, light and heavy springs arranged in tandem in position to urge said element in a direction to open the throttle valve when the suctional force is below a predetermined value, and a variable movement-transmitting element in the said connection between the throttle valve and the said element, which will cause the throttle valve to be moved more slowly at points near its closed position than at its more nearly open positions.

16. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a conduit leading from the passageway at a point between the valve and the engine, a casing communicating with the conduit, an element in the casing movable under suctional forces in the conduit to move the valve toward closed position, light and heavy springs arranged in tandem in position to urge said element in a direction to open the throttle valve when the suctional force is below a predetermined value, and a variable movement-transmitting element in the said connection between the throttle valve and the said element, which will cause the throttle valve to be moved more slowly at points near its closed position than at its more nearly open positions, the said means comprising a crank element which is moved by a cam surface of changing radius along its crank-engaging area.

17. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a by-pass conduit around the valve, leading from the passageway at a point in advance of the valve to a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response tochanges in suctional force in the conduit and having operative connection with the throttle valve, a valve in the conduit at a position between the first-named point and said pipe, and means actuated upon predetermined changes in the rate of engine speed for moving the last-named valve, to vary the amount of fuel mixture moving through said conduit and to vary the suctional force exerted through said pipe, the by-pass being of suflicient size to permit the passage of substantial quantities of fuel mixture when the second-named valve is open.

18. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow of motive fluid to the engine, of a by-pass conduit around the valve, leading from the passageway at a point in advance of the valve to a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the easing movable in response to changes in suctional .force in the conduit and having operative connection with the throttle valve, a valve in the conduit at a position between the first-named point and said pipe, means actuated upon predetermined changes in the rate of engine speed for moving the last-named valve, to vary the amount of fuel mixture moving through said conduit and to vary the suctional force exerted through said pipe, the by-pass being of sufiicient size to permit the passage oi! substantial quantities of fuel mixture when the second-named valve is open, and a lost motion connection between the throttle valve and the second-named valve for limiting the extent to which the second-named valve may be opened relative to the throttle valve.

19. The combination with an engine having an intake passageway provided with a throttle I valve for controlling flow of motive fluid to the engine, of a by-pass conduit around the valve, leading from the passageway at a point in advance oi the valve to a point between the valve and the engine, a casing, a pipe leading from the conduit to the casing, an element in the casing movable in response to changes in suctional force in the conduit and having operasize to permit the passage of substantial quanti-,

ties of fuel mixture when the second-named valve is open, and a lost motion connection between the throttle valve and the second-named valve for limiting the extent to which the second-named valve may be opened relative to the throttle valve, such connection being so arranged that the second-named valve will not be completely closed through closing movement of the throttle valve.

20. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow to the engine, a head.- er chamber disposed peripherally of the passageway and communicating with the passageway through a plurality of ports that are located in advance of the valve, a similarly arranged header chamber communicating with the passageway through a plurality of ports at points between the valve and the engine, a by-pass conduit connecting the header chambers, a valve for controlling fiow in the conduit, a casing, a pipe leading from the conduit to the casing,.and an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve.

21. The combination with an engine having an intake passageway provided with a throttle valve for controlling flow to the engine, a by-pass conduit communicating with the passageway through a plurality of ports that are peripherally arranged in the passageway wall, in advance oi the valve, the conduit leading from the said ports into the passageway at a point between the valve and the engine, a valve for, controlling flow in the conduit, a casing, a pipe leading from the conduit to the casing, and an element in the casing movable in response to changes in suctional force in the conduit and having operative connection with the throttle valve.

GEORGE E. HOWARD. 

